Navigation menus lost page URL in 1.6>1.7 Upgrade

I upgraded to 1.7, following the steps from the documentation, and all went well until I noticed that the navigation menu links now show
/Contents/Item/Display/<id number> instead of the original URLs I added for each link via the Content Item "Browse" button in the navigation editing UI, before the upgrade.

Any ideas on how to correct this? (hopefully, w/o re-editing all 137 links) :/

The 1.7 query returns null for ContentMenuItemRecord_id, though; note the difference below in the generated table prefix as compared to the 1.6 query, where
Navigation has been replaced by Orchard_ContentPicker. Is this by design in 1.7? And, in any case, is their a recommended method to correct for this?:

Thanks! Since my last post I became familiar with the upgrade module (always wondered what exactly that did). Successfully migrated, and my menu items now working great. That makes me wonder about the other tabs on there, fields(1.5), Menu(1.5) and Routes(1.4),
but I'm hesitant to mess with success. Quit while I'm "behind" as it were. What's the risk of standing pat on those?